JPH0450587Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] This invention relates to a mounting device for a cylinder in which a rotating magnetic head is provided in a video tape recorder.

[Technical background of the invention]

FIG. 1 shows a conventional cylinder mounting device for a video tape recorder. FIG. 1a is a plan view of the cylinder seen from above, and FIG. 1b is a side view. In the figure, 11 is a cylinder, 12~
14 is a support body that supports the bottom surface of the cylinder 11. These supports 12 to 14 are connected to the main base 15
is fixed. To install the cylinder 11, after placing the cylinder 11 on the supports 12 to 14,
This is done by fastening the two together with screws. In this case, a screw hole is formed in either the cylinder 11 or the supports 12 to 14, and a hole for simply inserting a screw is formed in the other. Among the three holes for screw insertion, one hole has a diameter that is approximately the same as the diameter of the screw and functions as a positioning hole, but the other holes are larger than the diameter of the screw. This is to absorb the pitch tolerance between each screw hole and the pitch between each hole.

[Problems with background technology]

However, in the case of the above configuration, since the diameter of one of the three holes for screw insertion is set to approximately the same value as the diameter of the screw, rotation around the circumference of the cylinder 11 can be restricted; Since the diameters of the remaining two holes are larger than the diameter of the screw, there is an extremely high risk that the cylinder 11 will be misaligned at its mounting position if external forces such as vibrations or shocks are large. In order to prevent this positional shift, the tightening force of the screws may be increased, but if this is done, distortion may occur in the cylinder 11, which is a precision machined part.

[Purpose of invention]

This invention was made in order to cope with the above-mentioned circumstances, and aims to provide a cylinder mounting device that can prevent displacement of the mounting position of the cylinder without increasing the fastening force using screws or the like.

[Summary of the idea]

In this invention, a support body having a support part that supports the bottom surface of the cylinder is provided with a fitting part that fits into the side surface of the cylinder and prevents its position from shifting.

[Example of idea]

Hereinafter, one embodiment of this invention will be described in detail with reference to the drawings.

First, FIG. 2a is a plan view of the cylinder mounting device seen from above the cylinder, and FIG. 2b is a side view. In the figure, 21 is a cylinder, 22
24 is a support body, and 25 is a main base. The supports 22 to 24 are arranged at equal intervals around the circumference of the cylinder 21. In addition, each support 22
24 are support parts 221, 231, 241 that support the bottom surface 211 of the cylinder 21, and fitting parts 222, 232, 24 that fit into the side surface 212 of the cylinder 21.
It is integrally molded to have 2 parts. The cylinder 21 has a side surface 211 with fitting parts 222, 232,
After being placed on the support parts 221, 231, 241 of the supports 22 to 24 so as to fit with the support parts 242,
As shown in FIG.
It is fixed at 2-24. Although the support 23 portion is shown as a representative in FIG. 3, in reality the support 23 is shown as a representative.
The 2nd and 24th portions are also fastened with screws.
The screw 26 is screwed into a screw hole 213 formed in the cylinder 21 through a hole 233 formed in the support portion 231 of the support body 23 . Reference numeral 27 denotes a spring for enhancing the fastening effect of the screw 26, and is interposed between the screw head of the screw 26 and the support portion 231. Support 2
Among the holes for screw insertion provided in the supporting parts 221, 231, 241 of 2 to 24, one has a diameter that is approximately the same as the diameter of the screw 26, and has the function of regulating rotation around the circumference of the cylinder 21. (the above-mentioned one of the screw insertion holes and the screw 26 constitute at least a rotation regulating means), but the other two have a diameter larger than the screw 26, and the pitch between the screw insertion holes and the screw 26 are larger than the diameter of the screw 26. The pitch tolerance between the screw holes can be accommodated (the other two screw insertion holes and the two screws 26 constitute fastening means).

Note that the supports 22 to 24 are formed integrally with the main base 25, for example.

According to this embodiment described in detail above, the fitting portion 22
2, 232, 242 are the side surfaces 212 of the cylinder 21
This prevents the cylinder 21 from shifting due to external force, so there is no need to strengthen the fastening force by the screws 26, and distortion of the cylinder 21 can be prevented.

Moreover, it is sufficient to provide only the supports 22 to 24 in which the support parts 221, 231, 241 and the fitting parts 222, 232, 242 are integrally molded, and there is an advantage that the number of parts is no different from that of the conventional method.

Note that this invention is not limited to the previous embodiment.

For example, there may be four or more supports, or there may be one
Even if it is only one, it is sufficient that it exists entirely around the circumference of the cylinder 21.

Furthermore, if the movement of the cylinder 21 in the axial direction can be suppressed, the screw 26 may be fastened at only one location.

In addition, a hole is provided in the cylinder 21, and the support part 22
A screw hole may be provided at 1,231,241.

Moreover, the fastening with the screw 26 is performed between the side surface 212 of the cylinder 21 and the fitting portions 222, 2 of the supports 22 to 24.
32,242.

Alternatively, the screw 26 may have only a fastening function, and the rotation around the circumference of the cylinder 21 may be restricted separately. In other words, the diameters of all holes for screw insertion are made larger than the diameters of the screws. In this case, as a means for regulating the rotation around the circumference of the cylinder 21, the support portions 22 of the supports 22 to 24
1,231,241 or a protrusion provided on the main base 25 separately from the supports 22 to 24, and a protrusion on the bottom surface 211 of the cylinder 21 at a position opposite to the protrusion. The means may include holes or grooves formed to fit with the protrusions (see FIG. 4). In this case, the protrusion and the hole constitute the rotation regulating means, and the screw 26 and the hole for screw insertion constitute the fastening means. Note that the bottom surface 2 of the cylinder 21
21 is provided with a protrusion, and the support portions 2 of the supports 22 to 24 are
21, 231, and 241, or separately from these, a cylindrical member provided on the main base 25 may be provided with holes or grooves that fit into the projections. Further, the rotation regulating means using such projections and holes or grooves is provided on the side surface 212 of the cylinder 21.
and the fitting parts 222, 232, 2 of the supports 22 to 24
It may be provided between 42 and 42. When a rotation regulating means is formed between the side surface 222 of the cylinder 21 and the fitting portions 222, 232, 242 of the supports 22 to 24, this means has the effect of regulating the movement of the cylinder 21 in the axial direction. , there is a high possibility that the number of fastening points using screws can be reduced to one place.
In addition, in the above explanation, the protrusion is the cylinder 21.
It may be integrated with the supports 22 to 24, or
They may be press-fitted into holes formed in these.

Further, when one means has the function of fixing the cylinder 21 and the function of restricting rotation, like the screw 26 in the previous embodiment, an elastic body may be used instead of the screw 26. If you do this, the screw 26
There is no need for labor-intensive processing such as forming the screw hole 213 or making the diameter of at least one of the holes for screw insertion approximately equal to the diameter of the screw 26 as in the case of using the screw, and press-fitting the elastic body All you need to do is form a hole large enough to do so. In this way, the rotation regulating means of the cylinder is
It consists of a groove (groove, etc.) and a member (screw, protrusion, elastic body, etc.) that fits into the groove.

Of course, various other modifications can be made without departing from the gist of the invention.

Finally, the effectiveness of the fitting portion in the cylinder support in the present invention will be explained. By providing two protrusions for positioning the cylinder on the cylinder mounting base and two recesses that fit with the protrusions on the bottom of the cylinder, the fitting portion in the cylinder support of the present invention can be It seems that it is possible to prevent the cylinder from shifting with high precision, similar to regulating the position of the cylinder side surface. However, for the following reasons, the structure of the present invention is better in preventing displacement of the cylinder. Now, considering the causes of worsening misalignment, in the structure of the present invention, there are dimensional errors between the reference point on the base and the center position of the circle determined by at least three fitting points, the diameter of the circle mentioned above, and the diameter of the cylinder. There are only two sources of dimensional error: on the other hand,
In a structure in which the base has two protrusions for positioning the cylinder, there is a dimensional error between the reference point on the base and the center position of one of the protrusions (for the purpose of explanation, the protrusion is assumed to be a cylinder), Dimensional error between the center of the recess on the bottom (for the sake of explanation, the recess is assumed to be a cylinder) and the outer peripheral surface of the cylinder,
There are three factors: dimensional errors between the diameter of the protrusion and the hole diameter of the recess. From the above, the structure of the present invention is better able to prevent displacement of the cylinder.

[Effect of idea]

As described above, according to this invention, it is possible to provide a cylinder mounting device that can prevent displacement of the mounting position of the cylinder without increasing the fastening force using screws or the like.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a conventional cylinder mounting device, FIG. 2 is a diagram showing an embodiment of the cylinder mounting device according to this invention, and FIG. 3 is a diagram showing the relationship between the cylinder and the support in the device shown in FIG. FIG. 4, which is a diagram for explaining fixation, is a diagram showing another embodiment of the cylinder mounting device of the present invention. 21...Cylinder, 22-24...Support, 2
5... Main base, 211... Bottom, 212...
...Side surface, 221, 231, 241...Support part, 2
22, 232, 242...fitting portion, 233...
Hole, 213...Screw hole, 26...Screw, 27...
spring.

Claims (1)

[Claims for Utility Model Registration] A cylinder in which a rotating magnetic head is installed, a support part that supports the bottom surface of the cylinder, and a fitting that fits into the side surface of the cylinder at at least three points to prevent the cylinder from shifting. A cylinder support disposed on a base so as to have a mating portion; a recess provided between the cylinder and the cylinder support or the base so as to restrict rotation around the circumference of the cylinder, and a recess fitted therein; A cylinder mounting device comprising: rotation regulating means using mating members; and fastening means for fastening the cylinder and the cylinder support or base.